Moisture fail-safe system



Jan. 31, 1967 1 E. NovAK ETAL MOISTURE FAIL-SAFE SYSTEM 2 Sheets-Sheet lFiled Feb. 17, 1964 THOMAS J. HIGGINS ATTORNEY Jan. 31, 1957 E. NovAKETAL 3,301,211

MOISTURE FAIL- SAFE SYSTEM Filed Feb. 17, 1964 2 Sheets-Sheet 2 fo m 1-ln v o w g Q Q O a N. m n l!) MAGNETIC CLUTCH w LT- N INVENTORS:

LEO E. NOVA K THOMAS J. HIGGINS 0m/CMQ ATTORNEY TH EODORE W.QUAFINSTROMJRI United States Patent Filed Feb. 17, 1964, Ser. No.345,543 9 Claims. (Cl. 114-235) The present inventi-on relates generallyto safety devices for automatically placing a given apparatus in a safe,inoperative, or other preferred condition in event a predeterminedunsafe, hazardous, or destructive condition inadvertently occurs theretoand specifically it is `a fail-safe system for causing an underwatervehicle to surface in the event water enters the hull thereof or theelectrical power therein or thereto fails during normal operation.

In the past, underwater vehicles which became flooded or otherwisebecame incapacitated were sometimes lost, destroyed, or damagedconsiderably and thus made inoperative for most practical purposes.Als-o these adverse conditions sometimes occurred as a result of theirstriking the bottom of the sea, or a power failure prevented the properattitude and depth control which, in turn, resulted in loss of usefuloperation and possibly the vehicle itself.

The present fail-safe system constituting this invention substantiallyelimina-tes such adverse conditions by causing underwater vehicles tosurface in event any of the aforementioned troubles occur. Accordingly,it supplies the answer to a need long existing in the submarine art andsupplies it in a simpler, more effective, and more improved manner thanheretofore known.

It is therefore, an object of the invention to provide an improvedfail-.safe system.

Another object of this invention is to provide an improved method andmeans for effecting the surfacing of a towed submarine type vehicle inevent it becomes flooded with water, has a power failure, or approachestoo close to the sea floor for safety.

Still another object of this invention is to provide an improved methodand means for supplying predetermined control or command signals to avehicle disposed within an aqueous or other given environmental medium.

Another object of this invention is to provide a simple fail-safe systemthat is easily and economically constructed and maintained.

Other objects and many of the attendant advantages will be readilyappreciated as the subject invention becomes better understood byreference to the following detailed description when considered inconjunction with the accompanying drawing, wherein like referencecharacters designate correspondiing parts in the several views andwherein:

FIG. 1 is a block diagram `of the invention;

FIG. 2 is a diagrammatic representation of a unique power train foradjusting the control surfaces of -a vehicle incorporating the subjectinvention;

FIG. 3 is a schematic diagram of the electronic and electrical circuitsof the invention; and

FIG. 4 is a pictorial view of one type of vehicle which may contain anduse the invention to an advantage.

Referring now to FIG. 1, there is shown -a depth finder 11 of anypreferred conventional type, such as for instance a sonar set `or thelike, adapted for deter-mining the distance to the sea floor andproducing an electrical signal proportional thereto. The output of depthfinder 11 is supplied to a depth fail-safe circuit 12 which includes acathode follower circuit 13 and control amplifier circuit 14 connectedthereto. The output control amplifier 14 is coupled to actuating coil 15of a relay switch 16 for timely 3,301,211 Patented Jan. 31, 1967 Miceenergization thereof. A switch portion 17 of relay 16 is connected inseries with a pressure switch 18 and in parallel with a plurality ofwater detection electrodes 19. Actually, electrodes 19 occur in pairswhich act as switches, respectively, that conduct current therebetweenwhen immersed in kan electrically conductive fluid such =as sea water orthe like.

Electrodes 19 are yalso a part of the water-flooding 4failsafe portionof the invention and are connected in series with a rectifier 21 and anactuating coil portion 22 of another relay 23.

An alternating current power supply 24 is connected to said rectifier 21in such manner that the latter converts it to the direct currentnecessary for the energization of coil 22 whenever any appropriate pairof electrodes 19 are immersed in water, closing the circuit betweenthem.

In FIG. 2, it may be seen that a guidance system reversible motor 25 iscoupled through a magnetic clutch 26 to vehicle elevators 27 forproperly positioning them for vehicle control purposes during normaloperation.

Continuously connected to elevators 27 is `an up-position urging springdrive 28. As illustrated diagrammatically in FIG. 2, this spring driveis effectively connected to said elevators through any desired power orgear train such as, for example, a shaft 29, a worm `gear 31, a piniongear 32, and a shaft 33 which, in turn, is connected to elevators 27 formovement thereof. As can readily be seen, in this representativeembodiment, spring 28 is continuously connected between `a frame portionof the vehicle or other relatively fixed structure and the rotatableshaft which turns in both `directions t-o respectively up-position ordown-position elevators 27. 'Ihis spring is physically disposed in suchmanner that it is wound-up when said elevators are down-positioned :andunwinds when they are up-positioned. Hence, the resilient urging ofspring 28 is towards the unwind-elevator-upposition, regardless of theactual position of said elevators at any given instant. And, of course,spring 2S is sufficiently strong in torsion to 4move said elevators toan up position whenever the drive motor 25 is effectively disconnectedtherefrom Iby magnetic clutch 26, as will be explained in more detailsubsequently. In addition, it should be understood that reversible motor25 is strong enough to yovercome the unwinding force or torque of spring28 when it is driving elevators 27 t-oward a down position during normaloperation.

Magnetic clutch 26 is of the conventional type that causes disengagementand engagement when the electrical power is removed therefrom andapplied thereto, respectively. Connected betwen rectifier 21 andmagnetic clutch 26 is the switch portion 35 of relay 23 which timelyeffects the disengagement or engagement condition of magnetic clutch 26whenever switch 35 is open or closed, respectively, by actuating coil22.

Referring now to FIG. 3, the unique electronic circuit thereof is shownas having an input terminal 41 which is adapted for receiving theaforementioned depth finder output signal, and this terminal is coupledto the grid of a triode tube 42 that is disposed in a circuit isolationcathode follower circuit. The plate thereof is connected to a B+voltage. A resistor 43 is connected between the -cathode of triode 42and ground. A diode 44 is connected in series with a voltage dividernetwork consisting of series connected Variable resistor 45 and resistor46 and the total combination thereof is connected in parallel with theaforesaid resistor 43. The junction of resistors 45 and 46 is coupled tothe grid of a triode tube 47, with the plate `thereof coupled to oneterminal of actuating coil 15 of relay 16, discussed in connection withFIG. 1. The cathode of triode 47 is connected through parallel connectedZener diode 48 and resistor 49 to ground. The other terminal of coil 15is connected to B-tvoltage.

Switch 17 of relay 16 is either closed or open and in this case it isheld open so long as solenoid coil 15 is energized. Of course, thecircuitry of FlG. 3 discussed to this point makes up the aforementioneddepth failsafe circuit 12, explained briey supra in connection with FIG.l. The movable arm and the closed-switch contact of switch 17 arerespectively connected to electrical conductors Sti and 51, the formerof which is connected to hydrostatic pressure switch 1S and continues onto one terminal of relay actuating coil 22 and the latter of which isconnected to one of the output terminals of rectifier 21. Although manydifferent conventional rectifier' means may be employed in the subjectcircuit, this preferred embodiment includes `the conventional full-waverectifier design, containing diodes 52 through 55. The aforesaid pair orplurality of pairs of water detection electrodes is coupled betweenconductors Si) and 51. If more than one pair is used, such as would =bethe case if both the fore and aft parts of the vessel were beingmonitored for water flooding, the number of pairs thereof are connectedin Aparallel with each other. Thus, the shorting of any pair ofelectrodes closes the water-flooding fail-safe circuit at the oodinglocation, regardless of where it may be. Obviously, any number of pairsof water detection electrodes may be used without violating the spiritand scope of this invention, since so doing would be obvious to oneskilled in the art having the benefit of the teachings herein presented.

Switch 35 of relay 23 is a double-throw-double-pole switch with themovable arms 56 and 57 thereof respectively connected to oppositepolarity output terminals of rectifier 21. Contacts S through 62 arerespectively connected to the junction of extended conductor 50 and oneterminal of coil 22, open, and magnetic clutch 26. Accordingly, it maybe seen that relay 23 is so constructed as to be locked in the energizedcondition once it has been energized in the first place. The inputterminals of rectifier 21 are connected to the outputs of 110 voltalternating `current -power supply 24.

FIG. 4 depicts a typical towed submarine type vehicle 71 which mayadvantageously make use of the subject invention by having itincorporated therein as a fail-safe system. Many other types ofsubmarine vehicles may likewise employ this invention if so desired. Inthis particular case, the vehicle is of the type that is towed byanother ship or craft by means of a line or cable 72 which is capable ofbeing paid out and is of sufficient length to allow vehicle 71 `to rideat any desired depth. To insure stability of iiight, a plurality of fins73 are mounted on the rear thereof and, of course, elevators 27 aremounted thereon at any suitable position for attitude control purposes.Although in this instance, t-he elevators are shown as being located inthe front end of vehicle 71, they may obviously be incorporated as partof control surfaces or fins 73. Moreover, although vehicle 71 is hereinillustrated as an underwater vehicle, it should be understood that thesubject inventions use is not limited thereto and that land, air, orspace crafts may likewise use it to advantage with only minor designchanges to the detection electrodes 19 so as to make them operable asprobes or switches in any predetermined environmental medium. Likewise,the depth fail-Safe circuit may be uesd as is or so designed by theskilled artisan to be responsive to any given parameter or condition,since so doing would be obvious thereto having the benefit of theteachings herein presented.

All of the elements and components employed in this invention are wellknown and conventional per se and it is their new and uniqueinterconnection and interaction that effect the new and improved resultsobtained therefrom.

Briefly, the operation of the invention is as follows:

Actually, the invention as herein disclosed includes several fail-safecontrol-disconnect systems. One involves fail-safe operations whichoccur in event the submerged vessel approaches too close to the seafloor. Another concerns fail-safe operations which occur if waterflooding occurs at given vulnerable locations within the submergedvessel. And `stil-l vanother concerns fail-safe operations during powerfailure.

From a result standpoint, the subject invention merely positions theelevator control `surfaces to such a position that they cause thesubmerged vessel to rise toward the sea surface when any one or more ofthe aforementioned faults or conditions exist. Generally speaking, forinstance ,when the depth find-er indicates that the submerged vessel istoo close to the bottom of the sea, it produces a signal which whenapplied to depth fail-safe circuit 12 deenergizes coil 15 of relay 16and closes switch 17, thereby closing the circuit to coil 22 of relay 23to energize same and effect the opening of switch 35. The opening ofswitch 35 deenergizes magnetic clutch 26 and this puts motor 25 andelevator 27 in a disconnected condition.

Without the controlling force or torque of motor 25 to override theforce of spring 28, spring 28 unwinds and turns worm gear 31 and piniongear 33 in such direction to move elevators 27 to an up-position, which,of course, in turn, guides vessel 71 toward the surface as it is beingpulled along by the tractor ship.

As can be readily seen, due to the fact that magnetic clutch is in adisconnect condition when `no power is applied thereto, it willautomatically be placed in a disconnect condition in event a powerfailure ever occurs. Thus, another fail-safe operation inherently existsin the subject invention which increases its overall value.

On occasion, when the vessel 71 is traveling at less than ten feetdepth, it has been found to be necessary to disable the depth fail-safecircuit 12. This is because depth finders sometimes produce erroneousaltitude signals when the vehicle is at or near the sea surface, due toreflections from the air-water interface. Because these reflectionssignals give the erroneous apearance of being within some given distancesuch as, for instance, ten feet of the sea floor rather than the actualcondition of being within ten feet of the sea surface, and since thesubject depth failsafe circuit would cause the vessel to be surfacedunder such circumstances, it is disabled or effectively disconnected byhydrostatic pressure switch 18. This is easily accomplished by settingpressure switch 18 to open whenever the vehicle has less than said givendistance or exemplary ten feet depth. Of course, from the abovestatements it should be readily understood that a setting of ten feetdepth on switch 18 is merely exemplary, and any other operable settingmay be used as desired.

The water flooding aspect of the subject invention is very simple butmost effective. Whenever any of the pairs of water detection electrodes19 are immersed in water, it acts as a closed switch which energizescoil 22, opens switch 35, deenergizes magnetic clutch 26, and hencedisconnects elevators 27 from motor 25, allowing coil spring 28 to takeover and adjust elevators 27 to an up position to ultimately effectsurfacing of the towed vessel.

Referring to the detailed schematic of FIG. 3, it may be seen that thevessel depth information is applied to the grid of cathode follower 42and is coupled therefrom through diode 44 `and a voltage divider networkcomprising resistors 45 and 46. Diode 44, in this case, isolates thecathode bias circuit of triode 42 from triode 47. Variable resistor 45,in the voltage divider circuit, determines the voltage on the cathode oftriode 42 which is necessary in order to cause triode 47 to conduct.Because resistance 45 may be varied, the time of conduction of triode 47may be varied and, consequently, the maximum depth to which the vesselcan go without fail-safe operation occurring may be varied accordingly.Conduction of triode 47 actually occurs as a result of the aforesaidgrid signal supplied by the depth finde-r being of sufficient voltage tooverride the cutoff bias placed thereon by resistors 46 and 49.

Zener diode 48 regulates said cathode bias to a predetermined voltage,say of the order of twenty-two volts, when triode 47 is conducting.Because the plate of triode 47 is coupled through actuating coil 15 ofrelay 16 to a given B+ voltage, relay 16 is energized whenever triode 47conducts.

When the vehicle is too close to the bottom of the sea, the potential atthe cathode of cathode follower 42 is too small to cause a suicientplate current increase in triode 47 to operate relay 16. Thus, when thevehicle is operating at desirable or normal depths, relay 16 remainsenergized and switch portion 17 thereof is held open, and when thevehicle is operating at unsafe depths too close to the sea floor, relay16 is deenergized and switch 17 closes, ultimately causing theup-positioning of elevators 27.

Obviously, many modifications of this embodiment or other embodiments ofthe subject invention will readily come to the mind of one skilled inthe art having the benefit of the teachings presented herein inaccompaniment with the associated drawing. Therefore, it is to ybeunderstood that the invention is not to be limited thereto and that saidmodifications and other embodiments are intended to be included withinthe scope of the appended claims.

What is claimed is:

1. An automatic submarine vessel safety device comprising incombination,

a water depth fail-safe circuit,

a water detection means,

a magnetic clutch means adapted for being interposed between a drivemotor and a vehicle control surface in such manner that said motor -iseffectively connected to said vehicle control surface for the drivingthereof only when said magnetic clutch is energized,

means for energizing said magnetic clutch means, and

means interconnecting said water -depth fail-safe circuit, said waterdetection means, said magnetic clutch means, and the aforesaidenergizing means for disconnecting the latter from said magnetic clutchin response to a predetermined depth signal being supplied to said depthfail-safe circuit, and in response to water being detected by theaforesaid water detection means.

2. The device of claim 1 wherein said water depth failsafe circuitcomprises,

a diode,

a variable resistor with one terminal thereof coupled to said diode,

a ground,

another resistor with one terminal thereof joined to the other terminalof said variable resistor and the other terminal thereof coupled to saidground,

a triode having a grid, a plate, and a cathode with the grid thereofconnected to the junction of said variable and second mentionedresistors,

a Zener diode coupled between the cathode of said triode and saidground,

a third resistor connected in parallel with said Zener diode,

a B+ voltage, and

a relay having an actuating coil and a switch actuated by said actuatingcoil with the actuating coil thereof connected -between said B+ voltageand the plate of the aforesaid triode.

3. The device of claim 1 wherein said water detection means comprises atleast one pair of electrodes adapted for passage of electrical currenttherebetween when same submerged in water.

4. The device of claim 1 wherein said means for ener gizing saidmagnetic clutch means is an electrical power supply.

5. A depth-fail safe circuit for supplying an up-position command signalto a marine vehicle submerged within an aquaeous medium comprising incombination,

a cathode follower having an input and an output with the input thereofresponsive to an electrical signal corresponding to the depth of amarine vehicle,

a diode coupled to the output of said cathode follower,

a first resistor connected to said diode,

a ground, n

a second resistor interconnecting said first resistor and said ground,

a triode having a grid, a plate, and a cathode with the grid thereofconnected to the junction of said lirst and second resistors,

a Zener diode coupled between the cathode of said triode and saidground,

a triode resistor connected in parallel with said Zener diode,

a B+ voltage, and

a relay having an actuating coil and a switch operated by said actuatingcoil with the actuating coil thereof connected between the plate of saiddiode and said B+ voltage.

6. A depth fail-safe circuit for supplying an up-position command signalto a marine vehicle submerged with an aquaeous medium comprising incombination,

a cathode follower having an input and an output with the input thereofresponsive to an electrical signal corresponding to the depth of amarine vehicle,

a diode coupled to the output of said cathode follower,

a first resistor connected to said diode,

a ground,

a second resistor interconnecting said first resistor and said ground,

a triode having a grid, a plate, and a cathode with the grid thereofconnected to the junction of said first and second resistors,

a Zener diode coupled between the cathode of said triode and saidground,

a triode resistor connected in parallel with said Zener diode,

a B+ voltage,

a relay having an actuating coil and a switch operated by said actuatingcoil with the actuating coil thereof connected between the plate of saiddiode and said B+ voltage,

a magnetic clutch means, and

means interposed between said magnetic clutch means and the switch ofthe aforesaid relay for energizing said magnetic clutch means when saidswitch is in an open-condition.

7. The device of claim 6 wherein said means interposed between saidmagnetic clutch means and the switch of the aforesaid relay forenergizing said magnetic clutch means when said switch is in an opencondition comprises,

a power supply,

a rectier connected to said power supply,

a second relay having a second actuating coil and a second switch withthe second actuating coil connected between said rectifier and theswitch of said first mentioned relay in such manner that said secondactuating coil is energized when said lfirst mentioned relay switch isclosed and with said second relay switch connected between the switch ofsaid first mentioned relay and said rectifier and to the aforesaidmagnetic clutch in such manner that said magnetic clutch is energizedonly when said second relay switch is in closed condition.

8; The invention according to claim 7 further characterized by ahydrostatic pressure switch interposed between the switch of said firstmentioned relay and the actuating coil of the aforesaid second relay.

9. Means for directing a towed submarine vehicle toward the surface ofthe water in the event there is waterflooding thereof comprising incombination,

a pair of water detection electrodes,

a power source having a pair of outputs with one of the outputs thereofconnected to one of the aforesaid pairs of electrodes,

a magnetic clutch,

switch means coupled between the input of said magnetic clutch and theother output of said power source,

means connected between the other of said power source outputs and theother of said pair of water detection electrodes for actuating saidswitch means to an open condition when said pair of Water detectionelectrodes are immersed in water,

a guidance system drive motor,

elevator means effectively connected to said drive motor through saidmagnetic clutch when the latter is in an energized condition, and

means connected to said elevator means for resiliently urging sametoward an up position continuously and for the directing of saidsubmarine vehicle toward the surface of the Water when said resilienturging means is not overridden 'by the aforesaid drive motor as a resultof disengagement thereof from said ele-` vator means due to thedeenergization of said magnetic clutch.

References Cited by the Examiner MILTON BUCHLER, Primary Examiner.

T. M. BLX, Assistant Examiner.

1. AN AUTOMATIC SUBMARINE VESSEL SAFETY DEVICE COMPRISING INCOMBINATION, A WATER DEPTH FAIL-SAFE CIRCUIT, A WATER DETECTION MEANS, AMAGNETIC CLUTCH MEANS ADAPTED FOR BEING INTERPOSED BETWEEN A DRIVE MOTORAND A VEHICLE CONTROL SURFACE IN SUCH MANNER THAT SAID MOTOR ISEFFECTIVELY CONNECTED TO SAID VEHICLE CONTROL SURFACE FOR THE DRIVINGTHEREOF ONLY WHEN SAID MAGNETIC CLUTCH IS ENERGIZED, MEANS FORENERGIZING SAID MAGNETIC CLUTCH MEANS, AND MEANS INTERCONNECTING SAIDWATER DEPTH FAIL-SAFE CIRCUIT, SAID WATER DETECTION MEANS, SAID MAGNETICCLUTCH MEANS, AND THE AFORESAID ENERGIZING MEANS FOR DISCONNECTING THELATTER FROM SAID MAGNETIC CLUTCH IN RESPONSE TO A PREDETERMINED DEPTHSIGNAL BEING SUPPLIED TO SAID DEPTH FAIL-SAFE CIRCUIT, AND IN RESPONSETO WATER BEING DETECTED BY THE AFORESAID WATER DETECTION MEANS.